package com.itheima.reggie.controller;

import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {

    @Value("${reggie.path}")
    private String basepath;

    /**
     * 文件上传
     *
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file) {
        //file是一个临时文件，需要转存到指定位置，否则本次请求完成后临时文件会删除
        log.info(file.toString());

        //获取原始文件名
        String originalFilename = file.getOriginalFilename(); //xxx.jpg
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));//.jpg

        //使用UUID生成随机名称，防止因文件名相同造成覆盖
        String filename = UUID.randomUUID().toString() + suffix; //uuid.jpg

        //创建文件目录
        File dir = new File(basepath);
        if (!dir.exists()) {
            //目录不存在，需要创建
            dir.mkdir();
        }

        try {
            //将临时文件转存到固定路径存储
//            file.transferTo(new File("D:\\dishes.jpg"));

            file.transferTo(new File(basepath + filename));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(filename);
    }

    /**
     * 文件下载
     *
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response) {


        try {
            //输入流 通过输入流读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basepath + name));

            //输出流 通过输出流将文件写回浏览器 在浏览器展示图片
            ServletOutputStream outputStream = response.getOutputStream();

            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = fileInputStream.read(bytes)) != -1) {
                outputStream.write(bytes, 0, len);
                outputStream.flush();
            }

            //关闭资源
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
